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Punycode Converter

Encode an internationalized hostname to ASCII Punycode or decode xn-- labels to Unicode.

Free browser toolRuns in your browserNo sign-up
International domain workspace

Convert Unicode hostnames and ASCII Punycode labels

Encode an internationalized hostname for DNS-compatible display or decode xn-- labels back to readable Unicode without resolving the domain.

Unicode to ASCII

mode

15 B

input size

21 B

output size

Hostname only

14 characters

Converted hostname

21 characters

This converts hostname labels only. It does not perform DNS lookup, registration checks or phishing-safety validation.

Private by design. Input is processed inside this browser tab and is not sent to ToolsOnDuty.

About the Punycode Converter

Punycode Converter is a focused browser-based utility. Encode an internationalized hostname to ASCII Punycode or decode xn-- labels to Unicode.

The calculation runs locally in your browser, so the supplied value is not uploaded to ToolsOnDuty. The same capability is also available through the authenticated developer API.

Key features

  • Fast local processing with explicit validation
  • Copy-ready structured result
  • No account, upload or paid data provider required

How to use

  1. 1Enter a hostname without a path or protocol.
  2. 2Choose any available conversion or formatting options.
  3. 3Run the tool and review the encoded or decoded hostname.

Examples

Punycode Converter example
Input: a hostname without a path or protocol
Output: the encoded or decoded hostname

Frequently asked questions

Is my input uploaded?
No. This website tool runs in your browser. Only the optional public API version sends input to the authenticated API route.
Can I use this in an application?
Yes. The Developers documentation lists the authenticated endpoint, request parameters and response example.
Should I verify the result?
Yes. Deterministic tools are designed for repeatable results, but format-specific or heuristic output should still be checked for your use case.

Continue your workflow

Open a related tool to prepare your files or refine the finished result.